An operator of a vehicle may use a mobile device to perform a variety of vehicle functions. For example, the mobile device may communicate with the vehicle to start the vehicle or unlock a vehicle door. It is desirable to be able to perform these and other vehicle functions based in part on the operator's proximity to the vehicle. However, with respect to determining the operator's proximity, greater accuracy than is presently available is needed in order to perform desirable functions and improve the operator's vehicle experience. Thus, there is a need for a communication system capable of providing greater accuracy and reliability with respect to the operator's proximity, location, or both.